The proposed study has three central objectives: 1) an evaluation of the impact of the new Massachusetts mental health law on involuntary civil commitment of the mentally ill; 2) the preliminary development and evaluation of a "dangerous to others" assessment instrument; and 3) a survey of legal and psychological concepts of dangerousness and their relationship to social policy objectives. Subjects will be in-patients at the Massachusetts Mental Health Center, the Boston State Hospital, the Gardner State Hospital and Bridgewater State Hospital. Socio-demographic, clinical and behavioral variables will be studied with relation to their influence on decision- making for or against the release of patients. Patients will be interviewed by project staff and will be followed up one year later by direct interview and telephone. Court proceedings for subjects for whom involuntary civil commitment is sought will be observed and data collected relevant to the adequacy of the litigation, the adequacy of the protection of the patient's civil rights and the quality of the operation of the new Massachusetts mental health statute.